What we know about the new coronavirus strain --------------------------------------------------- Concerns are growing over a highly infectious strain of coronavirus that has emerged in the United Kingdom. The new variant, called B.1.1.7, is already present elsewhere in the world, scientists have warned --------------------------------------------------- Why variant is causing concern B.1.1.7 carries unprecedented number of mutations – changes in viral genetic code – and is rapidly replacing other versions of virus in parts of England --------------------------------------------------- Speed of transmission Variant up to 70 percent more transmissible than other strains in UK. R number – which indicates if epidemic is growing or shrinking – may be increased by Spike protein ACE2* receptor 0.4, making disease harder to control --------------------------------------------------- Geographical spread Across UK. Cases in other countries include Australia, Denmark and Netherlands. Similar variant has emerged in South Africa --------------------------------------------------- Symptoms: Broadly same – high temperature, persistent dry cough and loss of, or change in, taste and smell. B.1.1.7 not believed to be any more deadly, although increase in transmission could cause problems for hospitals. Vaccines should still be effective against new variant --------------------------------------------------- Virus mutation: Viruses commonly change through mutation, leading to emergence of new variants. Initial analysis of B.1.1.7 identifies two worrisome alterations to spike protein on virus surface --------------------------------------------------- SARS-CoV-2 virus Human cell Virus genome --------------------------------------------------- Infection: Virus relies on spike protein to bind to ACE2 receptor – entry point into human cell for virus to replicate --------------------------------------------------- N501Y mutation: Has previously been shown to increase how tightly protein binds to ACE2 receptor --------------------------------------------------- H69/V70 deletion: Makes survivors’ coronavirus antibodies less effective at attacking virus --------------------------------------------------- Sources: BBC, FT, Science Picture: CDC *Angiotensin-converting enzyme 2 © GRAPHIC NEWS